三江平原不同稻田土壤化学性质演变特征

Evolution Characteristics of Soil Chemical Properties in Different Types of Paddy Fields in Sanjiang Plain

[目的]明确三江地区不同类型稻田土壤化学性质演变特征。[方法]以三江平原地区主要种稻土壤草甸土、草甸黑土、白浆土为调查对象,采集0～40年不同种稻年限的土壤样本,开展不同种稻年限水田土壤化学性质演变规律的研究。[结果]不同类型土壤种稻后,土壤化学性质演变规律存在异同;3类土壤耕层有机碳含量随种稻年限增加均呈上升趋势;草甸土心土层和犁底层土壤有机碳含量种稻后上升,白浆土犁底层土壤有机碳含量种稻后上升,随种稻年限延长无变化,心土层有机碳含量种稻后下降;草甸黑土心土层和犁底层有机碳含量种稻后无增加趋势;草甸土和草甸黑土土壤中还原性物质总量种稻后在各层均增加,随种稻年限增加有上升趋势,白浆土土壤中还原物质含量在耕层和犁底层随种稻年限增加呈上升趋势;草甸土种稻后各层土壤Fe^(2+)、Mn^(2+)含量均增加,在种稻10年后向下移动,可达到心土层;草甸黑土种稻后各层土壤Fe^(2+)含量增加,Mn^(2+)仅在耕层有增加趋势;白浆土Fe^(2+)、Mn^(2+)含量在耕层和犁底层增加,在种稻10年后向下移动至犁底层。[结论]3类土壤在种稻过程中已具有向水稻土形成的一些特征。

[Objective]To clarify the characteristics of soil chemical properties in different types of paddy fields in Sanjiang area.[Method]The main paddy soil in Sanjiang Plain was taken as the research object,including meadow soil,meadow black soil and planosol.The soil samples of different rice growing years during 0-40 were collected,and the soil chemical properties of different rice growing years were studied.[Result]After planting rice in different types of soil,the evolution of soil chemical properties was different.The organic carbon content of three soil plough layers increased with the growing number of years.The soil organic carbon in subsoil and plow layers of meadow soil increased after planting rice.In planosol plough layer soil organic carbon increased after planting rice with no change in planting years,and the organic carbon in the subsoil decreased after planting rice.The organic carbon content of the meadow black soil in subsoil and plow bottom layers did not increase after planting rice.The total reducing substances in each layer of the meadow soil and meadow soil were increased after planting rice,and there was a rising trend with the increasing number of years.The reducing substances in the planosol plough layer and the plow bottom layer increased with the growing number of years.Fe2＋ and Mn2＋ content in each layer of the meadow soil were increased after planting rice,and Fe2＋ and Mn2＋ moved down in10 years after planting rice,and cloud reach the subsoil. After planting rice,the content of Fe2＋ in the soil layer of the meadow black soil increased,and the Mn2＋ only increased in the plough layer.The content of Fe2＋ and Mn2＋ increased in the plough layer and the plow bottom layer of the planosol,and Fe2＋ and Mn2＋ moved down to the plow bottom layer after planting rice for 10 years.[Conclusion]These three soils had some characteristics of paddy soil in the process of planting rice.